Antimicrobial Activity and Cytotoxicity of “Bang Chang” Thai Cultivar Chili Pepper (Capsicum annuum Var. acuminatum)

Abstract

Capsaicin is found naturally in the Solanaceae family of plants and linked to numerous health advantage. Capsaicin is also responsible for the antimicrobial properties of chili pepper. Thai Capsicum cultivar “Bang Chang chili pepper” (Capsicum annuum var. acuminatum), initially cultivated in Bang Chang subdistrict, Samut Songkhram, Thailand. This study aims to determine bioactive substances such as capsaicin and phenolic content, as well as antimicrobial activity against pathogenic bacteria, Staphylococcus aureus, S. epidermidis, Escherichia coli and Cutibacterium acnes) and yeast, Candida albicans, and cytotoxicity with human skin fibroblast cells. The TPC and capsaicin in the ethanol extract were 2.50 ± 0.13 mg GAE/g and 0.0104 ± 0.0 mg/100 mL, while in the oil extract were 0.0020 ± 0.0 mg/100 mL and 1.05 ± 0.05 mg GAE/g. Antimicrobial of this chili pepper was found in only oil extract that was inhibited against to C. albicans (inhibition zone = 10.68 ± 0.49 mm) There was preferrable when compared to fluconazole ((inhibition zone = 24.65 ± 0.25 mm). Both extracts (0.0001-1.0 mg/mL) had no effect on human fibroblast cells, implying that they are non-toxic. The finding may imply that non-pungent capsicum strains cannot inhibit bacterial growth due to low amount of phenolics and capsaicin contained. Capsicum variety and temperature of extraction were also affected on their property. As a result, oil extract was favored for C. albicans suppression. This pepper extract can be used as an antifungal agent, and a pharmaceutical formulation must be developed.